A number of expendable components having a finite life, such as an aluminum electrolytic capacitor, have hitherto been used in a power supply device, so that the power supply device itself has been considered as a component having its set life.
If a power supply device comes to an end of its life or if a power supply device is unexpectedly broken down resulting in a system down, a production line is stopped leading to a large influence on users, for example, leading to a prolonged down time.
Further, in recent years, in the market, there are ever-increasing demands from users that a life diagnosis function is provided in a power supply device, and the cost of maintenance is decreased by preventive maintenance during operation to shorten the down time.
A direct-current power supply device that can detect a time for replacement of a smoothing capacitor due to its life and can predict the life of the smoothing capacitor is disclosed in Patent Document 1.
Patent Document 1: Japanese Patent Application Laid-open No. H11-356036